Wednesday, October 28, 2015

The Reappearance of the Bluebirds - Part I

As you might remember, my neighbor mounted a Bluebird nest box in our yard last spring. By the first week of July, four Bluebird babies had hatched in the box. On the morning of July 22nd, I
knew that the babies were due to leave the nest soon.

Fortunately, it was sunny and
clear that morning; so I went outside and took numerous photos of the parents
feeding the babies inside the box.A couple of the photos even showed a baby or
two peeking out of the nest box hole.

That evening, to my great dismay,
there were no Bluebirds around the box or its vicinity!I
checked the inside of the box and found no babies there.The nest was compressed and quite unsanitary looking.

Apparently, the babies had
left the nest box (fledged) some time that day.I was unprepared for this because I had calculated that the following day would be fledging day and I would have one more day to photograph the babies peeking out of the box.

Prior to this past July, my experience with observing baby birds in a nest had been limited to Barn Swallows, as I have described
in my book, Bonding with the Barn Swallows.

Unlike baby Bluebirds, Barn Swallow babies, once they fledge, remain in the vicinity of their nest.In the days following the
fledging of Barn Swallow babies, I have often seen them high in the air,
quickly flapping their wings as they practice flying.They will often line up on the utility wires to
rest and wait to be fed by their obliging parents.

Also unlike baby Bluebirds, baby
Barn Swallows who have fledged during the morning will often return to the
nest that night in order to rest from their long day.Below is a photo from page 102 of my book,
showing two baby Barn Swallows after they had returned to the nest the evening
of the day that they fledged.They
looked so worn out that I thought they were about to expire!

To my great relief, however, after an hour had passed, the babies were sitting upright in the nest, looking like normal baby Barn
Swallows.They left the nest for good
the following morning.

But baby Bluebirds are “here
today, gone tomorrow”.They do not
return to their nest once they have left it.Their parents usher them into the trees for safety from predators.Unable to feed themselves, the babies must
depend on their parents to bring them insects for at least the next two weeks,
just as the parents do while the babies are still in the nest.

I would have liked to have witnessed
the fledging of the baby Bluebirds as an assurance that all four babies had made
it out of the box safely.We have a
number of roaming, feral cats around here, and I was quite concerned that one
or more of the babies had landed on the ground, making them vulnerable to predation.

A couple of mornings after fledging day, still not having seen any Bluebirds around, adult or young, I cleaned and sanitized the nest box. I had read that Bluebirds can raise two or three broods per season and that it might not be too late in the summer for the parent Bluebirds to start another brood. I had also read that a pair of Bluebirds likes to have their box clean and their old nest removed before they re-nest in the same box.

But the parent Bluebirds did
not return to their nesting area.In
fact, I did not see them anywhere!

I began searching the grounds
of the property where I live for any sign of Bluebird fledglings.But they were nowhere to be found.Then I remembered, as previously stated, that
parent Bluebirds take their newly-fledged babies into the woods to hide them
from predators.I had also read that, if
the mama Bluebird decides to build a new nest, she will proceed to the nesting
site and do so, leaving the papa to feed the young birds and teach them how to
hunt.

In an intense desire to find out how many babies had made it safely to their new home in the woods, I continued to search the property, paying close attention to the trees that border it. Finally, on the morning of July 31st, nine days after fledging day, I spotted a Bluebird on the wire above the neighbor’s property across the road. It appeared to be an adult male, but all I could get was a blurry photo, as shown on the left.

July turned into August, but
still, no Bluebirds.Where were
they? By August 6th, the two-week period of the fledglings’
dependence on their parents for food had passed.Had the fledglings survived?Were they now learning to hunt on their own?

At long last, on the morning of August 21st, 30 days after the Bluebird babies had fledged, I spotted a couple of Bluebirds on the fence at the far corner of the property. They were perching several feet from one another, apparently searching for insects on the ground.

One of the birds (see photo on right) had a considerable amount of blue on its back, along with a rust color on the side of its breast. However, its plumage was visibility mottled with small patches of white, showing that the bird was losing some of its feathers in preparation for growing new ones. This process is called "molting".

The bird looked like it might have been a juvenile in the process of gaining its adult plumage. However, if indeed a juvenile, it had not been hatched in our nest box because it appeared to be too mature. Perhaps it was an older juvenile that had fledged from another nest, possibly in early June. It displayed too much solid-colored plumage to have been be young enough to have been one of our babies.

The second bird (photo, below left) had a familiar look to it. At first I thought it was a juvenile because of the white spots on its breast. But, again, the bird definitely looked too mature to have been one of the babies that had left our box on July 22nd.

The familiar look was not from the bird's plumage. Rather, the bird’s fierce stance and alert personality jogged my memory. The bird was acting exactly as our mama bird had acted while her babies were in the nest – proud, yet vigilant, and seemingly prepared to attack anyone who would dare to venture close to her nest.

Could this possibly have been our
mama bird in molt?The white spots could be indicating that she had been shedding her summer coat in preparation for
gaining her winter plumage.

Suddenly, the bird left the fence and quickly flew to the utility wire on the other side of our building. I walked around the building to get a better view of it. The bird allowed me to get a couple of photos but remained in an alarmed and vigilant state, as you can see from the photo below:

Yes, this was definitely our mama bird! It had the same slate-colored head and upper back as our mama. In addition, her beak was relatively long in Bluebird terms. Mama had apparently recognized me while I was photographing her on the fence and must have become alarmed that I might be a threat to her young ones. It was as if she had flown up to the wire to get a better view of me to be certain that I was not there to harm her or the other Bluebirds.

So the mama was still alive! I was extraordinarily relieved and hopeful that she had done a good job of protecting her young. Given my observations of her personality over the summer, I assumed that she had done just that!

On the right is a photo of Mama Bluebird that I had taken
on July 16th while her babies were still in the nest box. She was
holding a worm in preparation to feed the babies, and you can see how
long her beak was. She was exhibiting the same stern and vigilant
stance as exhibited by the bird on the wire. Her plumage was a little
more colorful in this photo because she still had her summer coat.

The next evening (August 22nd), I noticed some birds perching on the distant wires across the hay field from my driveway (see photo below). The wires extend from a prominent, yet distant, telephone pole. My best count was seven birds. Although the birds looked like black dots to my naked eyes, my binoculars soon revealed that they were Bluebirds!

One by one, a Bluebird would
occasionally leave its perch on the wire and quickly swoop down to the ground, far
below, to gather an insect. Having harvested its prey, it would usually return to the wire to devour the insect. Once in a while, however, I would see a bird carry its insect from the ground to the top of the telephone pole
to smash the insect and make it more digestible, just as our mama and papa Bluebirds had done this past summer in order to prepare food for the youngsters.The birds on the wire whose
plumage patterns I could discern appeared to be adults.But, were some of the birds juveniles?I wondered if the visual acuity of a immature Bluebird would be sharp enough to allow it to be able to see an insect on the ground from the distance of a high utility wire.I did
not witness any of the birds feeding another bird, which made me assume that, if
juveniles were included on the wire, they were old enough to feed themselves.The questions remained:Did all four chicks fledge successfully from
our nest box and were they still alive?

The next day, August 23rd,
I again ventured to the far corner of the property to see if I could find any
juvenile Bluebirds.It had been one
month and one day since the babies had left the nest, and I had not yet seen a bird
that could have been one of them.Well, it must have been my lucky day because, as I approached the fence, I was delighted to see a bird perching there, and yes, it proved to be a young Bluebird! And it appeared to be the age that one of our babies would have reached by that time.

The photo at the above right shows the bird's "pin feathers", revealing it to be a juvenile. And, judging by the bright
blue feathers on the edge of its wing and part of its tail, it appeared to be a
male.The following day (August 24th), during the late afternoon, I was still
determined to find more juvenile Bluebirds, if possible. And I was not to be disappointed!

This time I spotted a juvenile female, as shown on the right side of the photo above. This particular juvenile appeared to be a female because her plumage lacked the blue that the previous day's juvenile male had displayed. You can see that the Bluebird on the left side of the photo is much more brightly colored.

As for the brightly colored Bluebird on the left side of the above photo, I could not discern its age. Despite the rich hues of its plumage, there were white spots throughout, indicating that the bird was molting. This bird was most likely the same bird I had seen on August 21st. Again, I could only guess that it was an older juvenile that fledged in June from another nest.

That same morning, I was able to get another
photo, shown below, of the brightly colored bird. this time perched on a high fence post. What a beautiful bright blue was on its
wings and back!

Part II will include a description of a special event that occurred in September and a revelation about the identity of one of the Bluebirds I spotted in August. You can follow this blog and be notified of the next post by entering your email address in the upper right corner.

If you have found this story interesting, you might want to check out my book, Bonding with the Barn Swallows. Its 117 photos include close-ups of the baby Barn Swallows that were hatched on my porch during 2011 and 2012. There are also photos of the parent swallows guarding the nest and feeding their young. As an extra bonus, the book includes photos of five different juvenile Barn Swallows, just ten days after fledging. You will be amazed at their varied markings. The book describes how one special male Barn Swallow communicated to me by his body language on the utility wire and how, only two days later, I discovered what he was trying to tell me. To find out more about the book and read a preview, just click on the image to the right.

Thanks so much for your comments, Christer! Wonderful that you have had so many young birds around! I'll admit, we are especially intense about our Bluebirds here in the eastern half of the US. Our Bluebird population began declining in the middle of the Twentieth Century due in large part to nest site competition from Sparrows and Starlings. Bluebird organizations began to form and urged people to put up nest boxes for them. The results have been quite rewarding, with Bluebird populations now on the increase in many regions!